Liquid metering pump



March 19, 1935. E ROY A- PRESCO'TT 1,995,268

LIQUID METERING PUMP Filed Jan. 22, 1952 I 2 Sheets-Sheet' 1 g ya Z -o 55 16. 17' Fiel Z7 v Z jZ Z7 Z5 zz a 29 Mrch 19, 1935.

LE ROY vA. PRESCOTT LIQUID METERING PUMP Filed Jan. 22, 1932 2 Sheets-Sheet 2 HGM 25? 55 Z5 .50 L 5 J9 ,5 y f J5 -I f w rf] "mi gb f? y -15 f 1`\ retenes Maf. 19, 193s l `1,995,268 l UNITED- sTATEs PATENT OFFICE LIQUID METERING PUMP Le Roy A. Prescott, Lyncott, Mich., assignor to Service Station Equipment Company, Conshohocken, Pa., a corporation of Delaware Application January 22, 1932, Serial No. 588,042

2 Claims. (Cl. 221-95) My invention is particularly applicable to base frame 2 having four feet 3. Said container pumps for dispensation of viscous liquids such as has the cover 5 also conveniently formed of sheet lubricating greases and including a portable conmetal with its downwardly turned flange 6 pertainer from which the liquid is elevated by a manently engaging the upper edge of said con- 5 pump comprising a reciprocatory piston operatainer 1. Said cover 5 has the liquid inlet opening 5 tively connected with a rotary crank. 'I'he grease 7 which is normally closed by the lid 8 which is is thus progressed step by step through a flow pivotally connected with said cover 5 at 9 and is meter including a rotary index pointer which adapted to be held in closed position by the screw traverses a circular graduated scale. Ordinarily, 10 provided with the Wing nut 11.

10 the intermittent reciprocation of the pump piston Said cover 5 carries, suspended in said conl0 permits the formation of bubbles and pockets of tainer 1, the pump cylinder 12. Said cylinder has,

air in the grease elevated from the container at the lower end thereof, the intake foot 13 prowhich cause a false manifestation of the amount vided with the foot valve 14 which is in fact a of grease dispensed through the meter if the air check valve which opens inwardly to permit in- 15 is allowed to remain thus occluded in the stream gress of grease but closes to prevent egress of l5 Aof grease forced through the meter. grease from said pump cylinder 12. Said pump Therefore, theprincipal object and effect of my cylinder 12 is carried by the single casting 16 invention is to provide simple and eicient means which forms a casing head for the pump projectfor eliminating the air from the grease during its ing exterior to said Container andY having the passage from the pump to the meter so that the handle 17 by which the whole structure is readily 20 meter shall accurately manifest only the actual portable. Said casing 16 has the annular flange volume of grease dispensed. As hereinafter de- 18 which is detachably rigidly connected with said scribed, my improved air releasing means includes container cover 5, conveniently by three bolts 19 a bypass conduit extending from the upper porextending through said ange and cover and setion of the passageway between the pump and the Cured by the nuts 20- 25 meter back into the container aside from the Said Casing 16 has the laterally eXteridirlg hOlpump. 'I'he construction and arrangement are low arm 22 inclosing the. liquid passageway 23, such that the air is squeezed from the stream of which is connected by the pipe nipple 24 With the grease in said passageway, at the region of said casing 25 0f the' iiOW meier having the liquid diS- bypass Conduit and escapes from said passageway charge outlet26 connected by the flexible hose 27 30 back into the container, accompanied by a comwith the liquid dispensing nozzle 28. Itis to be paratively small amount of grease, leaving the particularly noted that said meter being thus dipassageway fully charged with a solidstream of rectly connected with said casing head 16 for the grease from the region of said bypass to the pump is SOlely SuDDOrted by Said Casing S0 that meter. l the entire pump and its appurtenances may be 35 It iS Characteristic 0f the form 0f my invention assembled in connection with said casing 16 indechosen for illustration that the air release bypass pendently Of the lid 5 fOr Said liquid Container 1, is embodied in a single casting which forms the thus materially lessening the 00st 0f prOduCtiOn head of the pump structure projecting from the of my apparatus aS Campared With apparatus 0f grease container and carried by a cover for the the prior art in which the meter is attached to 40 latter; said casting being provided with a handle and supported by the lid 0f the Container indeby which the whole apparatus is readily portable. pendently 0f the Pump, thus necessitating the A 'My invention includes the various novel feaemployment 0f pipe ttings including a union for tures of construction and arrangement hereinconnecting the pump and meierf after more definitely. specified. Said iiow meter casing 25 contains a rotary 45 In said drawings; Fig. I is a perspective view of member which is displaced by the'lOW 0f liquid a liquid metering pump conveniently embodying therethrough and operatively connected with the my invention. shaft 30`carrying the index pointer 31 which is Fig. II is a plan view of said pump. adapted to traverse a circular series of gradua- Fig.lI[ is avertical sectional View of said pump tions in the indicator casing 33 to manifest the' 50 taken on the line III, III, in Fig. I in the direction volume of liquid dispensed through said meter. of the arrows on said line. Said pump head casing 16 has the journal bear- In said figures; 1 is the liquid container' coning 34 for the'inner end of the crank shaft 35 veniently formed as a cone of sheet metal having which is also journaled in the stuiing box bearits truncated apex tightly fitted in the annular ing 36 and is provided with the crank lever 37 at 55 may be conveniently rotated. Said shaft 35 has the gear 39 between its bearings in mesh with the reciprocatory rack bar 40 which is mounted to reciprocate in said casing 16 in engagement with the slide bearing 41; which is shown in dotted lines in Fig. II on the side of said'rack opposite to said gear 39 and which is formed in said casting 16 upon the side of the latter-which is cut away in Fig. III. 'I'he upper limit of the movement of said rack is determined by the axial adjustment of the stop screw 42 which is in screw threaded engagement with the top of said casing 16 and held in adjusted position by the nut 43. Such adjustable means permits the operator to precisely predetermine the volume of liquid taken into the pump cylinder 12 and dispensed therefrom at each stroke of said rack limited by said stop screw.

Said rack 40 is rigidly connected with the piston'rod 45 which carries the piston 46 which is mounted to reciprocate in liquid tight relation with said pump cylinder 12 but has the liquid ports 47 extending through it controlled by the check valve 48 which works in opposition to the check valve 14.

. The arrangement above described is such that when said crank shaft 35 is turned, drawing said rack 40 upwardly, said piston valve 48 is closed but said footl valve 14 is opened to permit grease to be drawn into the cylinder 12 from the container 1. However, when said shaft 35 is turned to thrust said rack 40 downwardly; said foot valve 14 is closed by the back pressure of grease above it and said piston valve 48 opened to permit the grease between the two'valves to ow through the ports 47 in the piston to the space in the cylinder 12 above said piston. Such reciprocation of the rack 40 quickly fills the space above said piston 46, in the cylinder 12, casing 16, and parts in communication therewith, with grease having more or less air occluded therein in bubbles and pockets. However, the continued operation of said crank, as above described, so compresses the grease in the passageway23 in the arm 22 as to squeeze the air out of it and discharge the air back into the container through the bypass conduit 50 which extends lfrom the upper portion of said passageway 23 downwardly in communication with the interior of. said container 1 aside from the pump cylinder 12. Consequently, only a solid stream of liquid is discharged by the pump through the nipple 24 into the flow meter casing 25; so that the meter manifests only the actual amount of liquid dispensed therethrough.

Itmay be observed, that the elimination of air, or other gas, from the stream of liquid propelled by the pump is thus effected after the liquid has been discharged from the pump cylinder, but entirely within said pump casing head 16 and before said stream enters the fiow meter, so that said gas escape conduit is entirely independent of said meter, and that such elimination is effected without the interposition of any flow retarding valve between the pump piston and the discharge opening from the pump cylinder.

Such elimination of gas from the stream of liquid ls automatically effected by the pressure of the liquid necessary to dispense it; the release of the gas from the voids in the stream of liquid being effected by breaking the stream of liquid against the obstruction in the confined passageway 23 which is afforded by the gas escape conduit 50 which extends transversely to the stream of liquid in said passageway and is entirely n- 1,995,268 h its outer end having the handle 38 by which it closed and secluded in said casing 16; the pressure upon the liquid to dispense it serving to also force the liquid out through said obstruction.

Therefore, I do not desire to limit myself to the precise details of construction and arrangement herein setforth, as itis obvious that various' modifications may be made therein without departing from the essential features of my invention,-as defined in the appended claims.

1. In liquid dispensing apparatus, the combination with a container for a supply of liquid; of a removable lid for said container; a pump cyli`nder having a valved pump piston therein and a check valve at the bottom thereof; a single hollow casting, forming a pump casing head, rigidly but detachably secured on said lid and connected with the top of said cylinder suspending the latter in said container, from said lid, in spaced relation with the bottom of said container; a slide bearing in said casing, parallel with the axis of said cylinder; shaft bearings in said casing upon opposite sides of said slide bearing, and in coaxial relation with an axis transverse to the axis of said cylinder; a gear rack mounted to reciprocate in said slide bearing parallel with the axis of said cylinder and operatively connected with said piston; a gear in engagement with said rack; a shaft for said gear, journaled in said shaft bearings; a crank on said shaft, exterior to said casing; whereby said rack may be reciprocated to reciprocate said piston; a flow meter supported by said casing; a liquid passageway formed by and secluded in said casing, extending in communication with the interior of said cylinder and said flow meter; a gas escape conduit, extending parallel with the axis of said cylinder, within said passageway in said casing and supported at its lower end in said casing, in communication at its lower end with the' interior of said liquid container; said gas escape conduit being entirely secluded in s aid pump casing head and forming an obstruction in said passageway for breaking the stream of liquid and releasing the gas therefrom; whereby said gas escape conduit is rendered entirely independent of saidmeter and airand other gases are automatically eliminated from the stream of liquid entirely within said pump casing, merely by dispensing operation ofsaid pump, and fraudulent operation of said meter is precluded.

2. -In liquid dispensing -apparatus,the combination with a container fora4 supply of liquid; of a removable lid for said container; a pump cylinder having a valve pump piston therein and a check valve at the bottom thereof; a single hollow casting, forming a pump casing head, rigidly secured on said lid and connected with the top of said cylinder suspending the latterin said container from said lid, in spaced relation withthe bottom -of said container; a slide bearing in said casing,

tively connected with saidpiston; a gear in engagement'with said rack; a shaft for said gear, journaled in said shaft bearings; a crank on said shaft, exterior to said casing; whereby said rack may be reciprocated to reciprocate said piston; adjustable stop screw means in said casing in cooperative relation with the upper end of said rack; whereby the upper limit of the movement tainer; said gas escape conduit being entirely secluded in said pump casing head and forming an obstruction in said passageway for breaking the stream of liquid and releasing the gas therefrom; whereby said gas escape conduit is rendered entirely independent of said meter, and air and other gases are automatically eliminated from the stream of liquid entirely within said pump casing, merely by dispensing operation of said pump, and

fraudulent operation of said meter is precluded. l

LE ROY A. PRESCOTI'. 

